RFR: 8309346: Extend hs_err logging for all VM operations deriving from VM_GC_Operation

[Daohan Qu]

This patch implements `cause()` for `VM_GC_Operation` and its derived classes. It follows [JDK-8309210](https://bugs.openjdk.org/browse/JDK-8309210) to provide more detailed info for `VM_GC_Operation`s in hs_err log file.

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Commit messages:
 - Implement cause() for VM_GC_Operation and classes derived from it

Changes: https://git.openjdk.org/jdk/pull/14287/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=14287&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8309346
  Stats: 4 lines in 1 file changed: 4 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/14287.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14287/head:pull/14287

PR: https://git.openjdk.org/jdk/pull/14287